30 Helpful Python Snippets You Can Learn in 30 Seconds or Less

This article presents thirty concise Python code snippets that demonstrate common programming tasks, each accompanied by a brief explanation and example usage.

1. Duplicate Element Check

<code>def all_unique(lst):
    return len(lst) == len(set(lst))

x = [1,1,2,2,3,2,3,4,5,6]
y = [1,2,3,4,5]
print(all_unique(x))  # False
print(all_unique(y))  # True</code>

2. Anagram Check

<code>from collections import Counter

def anagram(first, second):
    return Counter(first) == Counter(second)

print(anagram("abcd3", "3acdb"))  # True</code>

3. Memory Size of Variable

<code>import sys
variable = 30
print(sys.getsizeof(variable))  # 24</code>

4. Byte Size of String

<code>def byte_size(string):
    return len(string.encode('utf-8'))

print(byte_size(''))          # 0
print(byte_size('Hello World'))  # 11</code>

5. Print String N Times

<code>n = 2
s = "Programming"
print(s * n)  # ProgrammingProgramming</code>

6. Capitalize First Letter of Each Word

<code>s = "programming is awesome"
print(s.title())  # Programming Is Awesome</code>

7. Chunk List into Fixed Size

<code>from math import ceil

def chunk(lst, size):
    return list(map(lambda x: lst[x*size:x*size+size], range(0, ceil(len(lst)/size))))

print(chunk([1,2,3,4,5], 2))  # [[1, 2], [3, 4], [5]]</code>

8. Compact List (Remove Falsy Values)

<code>def compact(lst):
    return list(filter(bool, lst))

print(compact([0, 1, False, 2, '', 3, 'a', 's', 34]))  # [1, 2, 3, 'a', 's', 34]</code>

9. Unpack Paired List

<code>array = [['a', 'b'], ['c', 'd'], ['e', 'f']]
transposed = zip(*array)
print(list(transposed))  # [('a', 'c', 'e'), ('b', 'd', 'f')]
</code>

10. Chain Comparison

<code>a = 3
print(2 < a < 8)   # True
print(1 == a < 2) # False
</code>

11. Join List with Commas

<code>hobbies = ["basketball", "football", "swimming"]
print("My hobbies are: " + ", ".join(hobbies))
# My hobbies are: basketball, football, swimming
</code>

12. Count Vowels

<code>import re

def count_vowels(s):
    return len(re.findall(r'[aeiou]', s, re.IGNORECASE))

print(count_vowels('foobar'))  # 3
print(count_vowels('gym'))     # 0
</code>

13. Decapitalize First Character

<code>def decapitalize(string):
    return string[:1].lower() + string[1:]

print(decapitalize('FooBar'))  # fooBar
</code>

14. Deep Flatten List

<code>def spread(arg):
    ret = []
    for i in arg:
        if isinstance(i, list):
            ret.extend(i)
        else:
            ret.append(i)
    return ret

def deep_flatten(lst):
    result = []
    for item in lst:
        if isinstance(item, list):
            result.extend(deep_flatten(item))
        else:
            result.append(item)
    return result

print(deep_flatten([1, [2], [[3], 4], 5]))  # [1, 2, 3, 4, 5]
</code>

15. List Difference

<code>def difference(a, b):
    return list(set(a) - set(b))

print(difference([1,2,3], [1,2,4]))  # [3]
</code>

16. Difference by Function

<code>def difference_by(a, b, fn):
    b_mapped = set(map(fn, b))
    return [item for item in a if fn(item) not in b_mapped]

from math import floor
print(difference_by([2.1, 1.2], [2.3, 3.4], floor))  # [1.2]
</code>

17. Chain Function Call

<code>def add(a, b):
    return a + b

def subtract(a, b):
    return a - b

a, b = 4, 5
print((subtract if a > b else add)(a, b))  # 9
</code>

18. Check for Duplicates

<code>def has_duplicates(lst):
    return len(lst) != len(set(lst))

print(has_duplicates([1,2,3,4,5,5]))  # True
print(has_duplicates([1,2,3,4,5]))    # False
</code>

19. Merge Two Dictionaries

<code>def merge_two_dicts(a, b):
    c = a.copy()
    c.update(b)
    return c

a = {'x':1, 'y':2}
b = {'y':3, 'z':4}
print(merge_two_dicts(a, b))  # {'x': 1, 'y': 3, 'z': 4}
</code>

20. Convert Two Lists to Dictionary

<code>def to_dictionary(keys, values):
    return dict(zip(keys, values))

keys = ["a", "b", "c"]
values = [2, 3, 4]
print(to_dictionary(keys, values))  # {'a': 2, 'b': 3, 'c': 4}
</code>

21. Enumerate List

<code>lst = ["a", "b", "c", "d"]
for index, element in enumerate(lst):
    print("Value", element, "Index", index)
</code>

22. Measure Execution Time

<code>import time
start_time = time.time()
# code to measure
end_time = time.time()
print("Time:", end_time - start_time)
</code>

23. Try/Except with Else

<code>try:
    2 * 3
except TypeError:
    print("An exception was raised")
else:
    print("Thank God, no exceptions were raised.")
</code>

24. Most Frequent Element

<code>def most_frequent(lst):
    return max(set(lst), key=lst.count)

print(most_frequent([1,2,1,2,3,2,1,4,2]))  # 2
</code>

25. Palindrome Check

<code>def palindrome(string):
    from re import sub
    s = sub('[\W_]', '', string.lower())
    return s == s[::-1]

print(palindrome('taco cat'))  # True
</code>

26. Operator Dictionary for Arithmetic

<code>import operator
action = {"+": operator.add, "-": operator.sub, "*": operator.mul, "/": operator.truediv, "**": pow}
print(action['-'](50, 25))  # 25
</code>

27. Shuffle List (Fisher‑Yates)

<code>from copy import deepcopy
from random import randint

def shuffle(lst):
    temp = deepcopy(lst)
    m = len(temp)
    while m:
        m -= 1
        i = randint(0, m)
        temp[m], temp[i] = temp[i], temp[m]
    return temp

print(shuffle([1,2,3]))
</code>

28. Expand List Including Sublists

<code>def spread(arg):
    ret = []
    for i in arg:
        if isinstance(i, list):
            ret.extend(i)
        else:
            ret.append(i)
    return ret

print(spread([1,2,3,[4,5,6],[7],8,9]))  # [1,2,3,4,5,6,7,8,9]
</code>

29. Swap Two Values

<code>def swap(a, b):
    return b, a

a, b = -1, 14
print(swap(a, b))  # (14, -1)
</code>

30. Dictionary Get with Default

<code>d = {'a': 1, 'b': 2}
print(d.get('c', 3))  # 3
</code>

These snippets provide quick, reusable solutions for everyday Python programming challenges.